主講人：趙慧、楊國星TianjinLightIndustryVocationalTechnicalCollege1.DrawingThreadsPartIIntroductiontotheLessonPARTIIntroductiontotheLessonThread

PartIIStructureofThreadsPARTIIStructureofThreadsOnthesurfaceofacylinder(orcone),thecontinuousprotrusionsandgroovesthatfollowahelicalpathandhavethesamecross-sectionalshapearereferredtoasthreads.

Externalthreadsarethreadsformedontheoutersurfaceofacylinder(orcone).ExternalThreadsInternalThreadsInternalthreadsarethreadsformedontheinnersurfaceofacylinder(orcone).StructureofThreads0104020305ThreadProfilePitchandLeadThreadDiameterNumberofThreadsThreadDirectionStructuralElementsofThreads:FiveKeyElementsThethreadprofile,diameter,andpitcharethemostfundamentalelementsthatdeterminethestructuralspecificationsofthread.Threadswhosethreefundamentalelementsconformtonationalstandardsarereferredtoasstandardthreads.Threadswithathreadprofilethatdoesnotconformtonationalstandardsarereferredtoasnon-standardthreads.StructureofThreadsTriangularTrapezoidalSawtoothOnthesectionalviewtakenalongtheaxisofthethread,thecontourshapeofthethreadisreferredtoasthethreadprofile.Commontypesofthreadprofilesincludetriangular,trapezoidal,andsawtoothshapes.01ThreadProfileStructureofThreadsThediametersofathreadincludethemajordiameter,theminordiameter,andthepitchdiameter.Lowercaselettersareusedtorepresentexternalthreads,whileuppercaselettersareusedtorepresentinternalthreads.Thenominaldiameterofathreadreferstoitsmajordiameter.MinorDiameterD1MajorDiameterDMinorDiameterd1MajorDiameterd02ThreadDiameterStructureofThreadsSingle-threadDouble-threadThreadsareclassifiedintosingle-threadandmulti-threadtypes.Athreadformedalongasinglehelicallineiscalledasingle-thread.Athreadformedbytwoormorehelicesthatareevenlydistributedalongtheaxisiscalledamulti-thread.Thenumberofthreadsisdenotedbyn.03NumberofThreadsStructureofThreadsTheaxialdistancebetweentwopointscorrespondingtoadjacentthreadsonthemid-diameterlineofthethreadiscalledthepitch,denotedbyP.Thedistancemovedaxiallyafteronecompleterevolutionalongthesamehelicallineiscalledthelead,denotedbyPh.Forsingle-threaded,thepitchisequaltothelead:P=Ph

Formulti-threaded,thepitchmultipliedbythenumberofthreadsisequaltothelead:Ph=P×numberofthreads(n).04PitchandLeadStructureofThreads05DirectionofThreadRotationThreadsareclassifiedintoleft-handedandright-handedtypes.Athreadthatrotatesclockwiseiscalledaright-handedthread,whiletheoppositeiscalledaleft-handedthread.Themostcommonlyusedistheright-handedthread.Todeterminethedirectionofthreadrotation,onecanpositiontheaxisvertically.Ifthevisiblepartofthethreadrisesfromlefttoright,itisaright-handedthread;ifitrisesfromrighttoleft,itisaleft-handedthread.Left-handedthreadRight-handedthread

PartIIISpecifiedDrawingMethodsforThreadsPARTIII1.DrawingMethodforExternalThreadsMinordiameter=0.85ofmajordiameterMajordiameterMinordiameter30°RootLineThreadRootRadius:Drawasa3/4fine-linecircle.TherootlineisdrawnintothechamferThreadTerminationLineThreadTailCrestLineThreadCrestRadiusChamferRadius:Payattentiontothedrawingofthethreelines:CrestLine,RootLine,ThreadTerminationLineDonotdraw!SpecifiedDrawingMethodsforThreads2.MethodofDrawingInternalThreadsdonotdraw!Chamferedcircle,Minordiameter=0.85ofmajordiameterMinordiameter30°RootlineRootcircle,drawa3/4thin-linecircleThreadterminationlineThreadtailCrestlineCrestcircleMajordiameterSectionlinesdrawntothicksolidlinePayattentiontothedrawingofthethreelines:CrestLine,RootLine,ThreadTerminationLineSpecifiedDrawingMethodsforThreads3.DrawingMethodforBlindThreadedHoles120°

Drilltheholefirst

ThentaptheholeHoledepth:H0.5DThreaddepth:hDrawingMethod鉆頭TappingtoolSectionlinesshouldbedrawntothicksolidlines.SpecifiedDrawingMethodsforThreadsDrawingofThreadedConnectionsSpecifiedDrawingMethodsforThreadsScrew-indepthNosectionviewisrequiredNote:1、Whendrawing,ensurethatthemajorandminordiametersoftheinternalandexternalthreadsarealigned.2、Sectionlinesshouldbedrawntothicksolidlines.Internalandexternalthreadsareusedinpairs.Onlywhenthefiveelements—threadprofile,diameter,pitch,numberofthreads,anddirectionofrotation—areidenticalbetweentheinternalandexternalthreadscantheybescrewedtogether.SpecifiedDrawingMethodsforThreadsDrawingExternalThreadsDeterminethepositionoftheinternalthread'sendfaceDrawtheinternalthreadandtheprojectionoftheremainingparts0.5D0.5DSummaryofthisLectureElementsofThreadStructure01DrawingInternalandExternalThreads02DrawingThreadConnections03ThinkingQuestionAADrawthethreadconnection,wherethenominaldiameterofthethreadis10mmandtheengagementlengthis20mm.主講人：趙慧、楊國星TianjinLightIndustryVocationalTechnicalCollege2.DrawingofBoltConnectorPART01Part1IntroductionClassIntroductionHaveyoueverseenboltconnector?FeaturesofBoltConnectorAbletowithstandlargeloadsPartreplacementAconnectorshouldnotbetoothick;Itcandrillthroughholes.Dismountable03

0104

02Part2AssemblyProcessofBoltConnectorPART02AssemblyProcessofBoltConnector01Passthroughtheholeoftheconnectedpiece02Putonthegasket03TightenthenutSectionViewofBoltConnectorThrough-holediameterNominalDiameterOfBolt>Part3SpecifiedRepresentationofBoltConnectorPART03TwoRepresentationofBoltConnetcorlook-uptableMeasuretheexactsizeofeachstructure

basedonthecorrespondingstandardthroughfastenercode.ScalingDrawingAlldimensionsexceptboltlengthareproportionaltothenominaldiameterofthethreadBoltGB/T5782-2016M12×60GasketGB/T97.2-200212ScrewNutGB/T6170-2015M12TediousandmeaninglessEasyanduniversalStuds,bolts,screwnutsandgasketsaredrawnasuncutRegulationsfromGB

1

2Theprocessstructureofthreadedfasteners,suchaschamfering,cuttinggroove,etc.,canbeomitted

Part4DrawingProcessofBoltConnectorPART04StepsofScalingDrawingDifferentpartshavedifferentprofilelinesThehrough-holediameterisdrawnat1.1timesthenominaldiameteroftheboltDrawthecenterlineStep1DrawtheconnectedpieceStep2

MainviewTopviewDrawtheboltStep3DrawthegasketStep4DrawthescrewnutStep5

StepsofScalingDrawingMainviewTopviewAttentionThedividinglinebetweentheupperandlowerpartsOutlineofthetwoconnectedpartsafteropeningholesOutlineoftheboltrodThreadthatisnotcoveredafterthescrewpassesthroughthehole

Part5DeterminationofNominalLengthofBoltPART05DeterminationofNominalLengthofBoltLBoltlength=thicknessoftwoconnectedparts+thicknessofgasket+nutthickness+reservedthicknessofboltprotrudingnut(0.3d)Thenominallengthoftheboltisestimatedaccordingtothefollowingformulat1t20.15d0.8d0.3d≈++++Assumethatthethicknessesofthetwoconnectedpartsaret1andt2TakethelengthgreaterthanandclosesttothestandardLt1t20.8d0.3d0.15dConclusionFeaturesofBoltConnector12DrawingofBoltConnectorAssemblyProcessofBoltConnector3ScalingDrawingofBoltConnectorQuestion①1Thesectionlinesoftwoadjacentpartsshouldbeinoppositedirections.2Agapshouldbedrawnbetweentheboltandtheunthreadedhole.3Thethreadlinesandthethreadterminationlinesshouldbedrawn.②③WrongCorrect主講人：趙慧、楊國星TianjinLightIndustryVocationalTechnicalCollege3.DrawingofScrewConnectionsPartIIntroductiontotheClassPARTIIntroductiontotheClassTheSpiritoftheScrewCharacteristicsofScrewConnectionsAThickerconnectionpartsshouldnotbedrilledasthroughholes.BCannot

withstandlargeloads.CNotintendedforfrequentdisassembly.Characteristics

PartIITheAssemblyProcessofScrewConnectionsPARTIIAssemblyofScrewConnections01Forthickerparts,machineblindthreadedholes;forthinnerconnectingpieces,machinethrough-holeswithcounterbores.02Thecounterborediametershouldbeslightlylargerthanthescrewheaddiameter.03Insertthescrewdirectlythroughthethrough-holeanddriveitintothethreadedhole.PartIIIDrawingProcessforScrewConnectionsPARTIIIDrawingStepsforScrewConnectionsFrontViewTopView1.1dExampleofaSlottedCountersunkScrewGB/T68-2016M10×30Drawthecenterline

DrawtheconnectedpartsThediameterofthethroughholeshouldbedrawn1.1timesthenominaldiameterofthebolt.Differentpartsshouldhaveinconsistentsectionlines.Thethreadedholeshouldbedrawnaccordingtothestandardmethodforinternalthreads,withspecialattentiongiventoensurethatthesectionlineisdrawntothethicksolidline.ABFrontViewTopViewbm0.5d0.5db

DrawtheconnectedpartsBThedepthofthethreadedholeisequaltothescrewengagementdepth（bm）+0.5d,wheredisthenominalthreaddiameter.Thevalueofbmisdeterminedbythematerialofthepartbeingthreadedinto: SteelintoSteel:bm=1d；

SteelintoCastIron:bm=1.25dor1.5d； SteelintoAluminumAlloy:bm=2dThedepthoftheunprocessedthreadedholeis0.5d.DrawingStepsforScrewConnectionsFrontViewTopView（Ananimationisneededhere:thescrewbeingscrewedintotheconnectorfromabove)LδtbmDrawingStepsforScrewConnectionsDrawingtheScrewCThescrewheadisdrawnaccordingtothedimensionalspecificationsofasinglescrew.Thenominalshanklengthisequaltotheconnectedpartthickness(δ)plus(+)theengagementdepth(bm)minus(-)thecounterboredepth(t).Inthetopview,thestraightslotinthescrewheadisdrawnata45°angletothecenterlineasspecifiedormaybesimplifiedbyusingathicksolidline.Notes:Thecounterboreshouldbeslightlylargerthanthescrewheaddiameter;twolinesareusedhere.Alineshouldbedrawntorepresentthecontactsurfacebetweenthetwoconnectedparts.Thethreadedportionshouldbedrawnaccordingtothemethodforexternalthreads.Thenon-threadedportionshouldbedrawnaccordingtothemethodforinternalthreads.SummaryofthislectureApplicationsandCharacteristicsofScrewConnections12Drawing

ScrewConnectionsAssemblyProcessofScrewConnections3DrawingProcessofScrewConnectionsReflectionQuestionHowmanyerrorsdidyounotice?1Thecountersunkholeshouldbeslightlylargerthanthediameterofthescrewhead,representedbytwolines.2Thesectionlinesoftwoadjacentpartsshouldbedrawninoppositedirections.3Fortheunthreadedportionofthethreadedhole,thedrawingmethodforinternalthreadsshouldbeused:thelargediametershouldberepresentedbyfinesolidlines,andthesmalldiameterbythicksolidlines.IncorrectCorrect①②③主講人：趙慧、楊國星TianjinLightIndustryVocationalTechnicalCollege4.DrawingofstudconnectionsPartIIntroductiontotheClassPARTIIntroductionBoltConnectionScrewConnectionTheconnectedpartmustnotbetoothicktoallowfordrillingathroughhole.Whenoneoftheconnectedpartsisrelativelythick,itisnotsuitablefordrillingathroughhole.Unabletobearalargeload.Notsuitableforfrequentdisassembly.Easytodisassemble.Capableofbearingalargeload.ApplicationScenariosforStudConnectionsStructuralconstraintsmakeitunsuitabletouseaboltconnection.Oneoftheconnectedpartsisrelativelythickandcannotbedrilledintoathrough-hole.Frequentdisassemblymakesitunsuitabletouseascrewconnection.03

0102PartIIAssemblyProcessofDouble-EndStudConnectionsPARTIIAssemblyProcessofDouble-EndStudConnectionsScrewthestudintothethreadedholeofthethickerconnectedpart.Placetheconnectedpartwiththethroughholeontothestud.Addthespring

washer.Tightenthenuttosecuretheconnection.PartIIIDrawingProcessofDouble-EndStudConnectionsPARTIIIDrawingStepsforDouble-EndStudConnectionsFrontViewTopView

DrawthecenterlineA

DrawtheconnectedpartsThediameterofthethroughholeshouldbedrawn1.1timesthenominaldiameterofthebolt.Differentpartsshouldhaveinconsistentsectionlines.Thethreadedholeshouldbedrawnaccordingtothestandardmethodforinternalthreads,withspecialattentiongiventoensurethatthesectionlineisdrawntothethicksolidline.BDrawingStepsforDouble-EndStudConnectionsFrontViewTopViewbbm0.5d0.5d

DrawtheconnectedpartsBThedepthofthethreadedholeisequaltothescrewengagementdepth（bm）+0.5d,wheredisthenominalthreaddiameter.Thevalueofbmisdeterminedbythematerialofthepartbeingthreadedinto:

SteelintoSteel:

bm=1d；

SteelintoCastIron:bm=1.25or1.5d；

Steelinto

Aluminum

Alloy:bm=2dThedepthoftheunprocessedthreadedholeis0.5d.DrawingStepsforDouble-EndStudConnectionsFrontViewTopView

Drawthedouble-endstudC

Drawthespring

washerD

DrawthenutELThenominallengthofthestud,L=thicknessoftheconnectedpartδ+thicknessofthewashers+thicknessofthenutk+thereservedthicknessfortheboltprotrudingfromthenut0.3d.Thenominallengthoftheboltisestimatedusingthefollowingformula.δ0.2d0.8d0.3d≈+++Assumethatthethicknessoftheconnectingpartwithathroughholeisδ.Refertothetableandchoosethestandard-lengthvaluethatisgreaterthanandclosesttothecalculatedlength.Lδs0.3dks=0.2d,

k=0.8dDeterminationofNominalLengthDrawingStepsforDouble-EndStudConnectionsNotesThespringwashershouldbedrawninthediagramatanangleof60°tothehorizontalline,withtwolinespointingupwardtotheleftanddownwardtotheright.Thethreadterminationlineatthescrewedendofthestudshouldalignwiththematingsurface,indicatingfullengagementandadequatetightening.Thethreadedportionshouldbedrawnaccordingtothestandardmethodforexternalthreads,"coarseontheoutside,fineontheinside.Theunthreadedportionshouldbedrawnaccordingtothestandardmethodforinternalthreads,"fineontheoutside,coarseontheinside.SummaryofthisLecture:ApplicationsandCharacteristicsofDouble-EndStudConnections01AssemblyProcessofDouble-EndStudConnections02DrawingProcessofDouble-EndStudConnections03THINKINGQUESTIONSHowmanyerrorsdidyoufind?1Threadlinesconcealedbythenutandwashershouldbeerased.2Theslotorientationofthespringwashershouldberepresentedbytwolinesinclinedat60°tothehorizontal,oneslopingupwardtotheleftandtheotherdownwardtotheright.3Thethreadterminationlinemustbeflushwiththecontactsurfacesofthetwoconnectedparts,indicatingfullengagementandsufficienttightening.IncorrectCorrect4Sectionlinesshouldbedrawntothethicksolidline.①①②②③③④④主講人：趙慧、楊國星TianjinLightIndustryVocationalTechnicalCollege5.DrawingKeyandPinConnections.PartI

IntroductiontotheClassPARTIIntroductiontotheClassHowdothepulleys,gears,etc.,inthediagramachieverotation?HubConnectionIntroductiontotheClassKeyConnectionPinConnectionPartIIDrawingMethodsforKeyConnectionsPARTII

Inmachinery,keysareusedtoconnectashaftandthecomponentsontheshaft(suchasgears,pulleys,etc.),allowingthemtorotatetogetherandtransmittorque.Thistypeofconnectioniscalledakeyconnection,andkeysarestandardmachineelements.ClassificationofKeysRectangularKeyWoodruffKeyGib-headWedgeKeySpecificationMarkingofParallelKeysNameTypesExampleIllustrationMarking

ExamplesStandardParallelKeyTypeATypeBTypeCForaround-headstandardparallelkeywithb=18,h=11,L=100:GB/T1096-2003Key18×11×100Forasquare-headstandardparallelkey(TypeB)withb=18,h=11,L=100:GB/T1096-2003KeyB18×11×100(TheBshouldnotbeomitted)Forasingleround-headstandardparallelkey(TypeC)withb=18,h=11,L=100:GB/T1096-2003KeyC18×11×100(TheCshouldnotbeomitted)DrawingMethodforParallelKeyConnectionsDrawingMethodforParallelKeyConnectionsThereisaclearancebetweenthesetwosurfaces;twolinesshouldbedrawn.WorkingSurfaceSectionlinesforadjacentpartsmusthaveoppositehatchdirectionsordifferentspacing.DrawingMethodforParallelKeyConnectionsdd-t1LbDrawingMethodandDimensionalNotationofKeywaysontheShaftKeywayDepthontheShaftKeyway

WidthDrawingMethodforParallelKeyConnectionsbDD+t2t2andbcanbefoundinthestandardsbasedontheholediameterD.DrawingMethodandDimensionalNotationofKeywaysontheHubKeywayDepthontheHubKeyway

WidthPartIIIDrawingMethodofPinConnectionsPARTIIIPinsarestandardpartsprimarilyusedforconnectingandpositioningcomponents.Commontypesinclude:CylindricalPinTaperedPinforconnectionforpositioningClassificationandFunctionofPinsDrawingMethodandMarkingforCylindricalPinConnectionsNotationofCylindricalPinHolesonDrawingsShaftGearPinperGB/T119–8×40?8pinholetomatewithpartXXCylindricalPinConnectionConepinholeΦ8formatchingPinGB/T117A8×30DrawingofconepinconnectionConepinholenotationonthedrawingConePinConnectionThinkingQuestionPracticedrawingkeyconnection主講人：趙慧、楊國星TianjinLightIndustryVocationalTechnicalCollege6.DrawingaGearPartIIntroductiontotheClassPARTIIntroductiontotheClassGearsarewidelyusedtransmissioncomponentsinmachinery;bymeansofgeardrives,onecantransmitmotionandtorque,andalterboththespeedanddirectionofmotion.PartIIBasicKnowledgeofGearsPARTIIOverviewTheteethofagearareraisedpartsonthegearthatfitintothecorrespondingspacesbetweenthematchinggear'steeth.Theirshapeensuresthatonegeardrivesthemotionofanothergear.Theteethofapairofgearsalternatelyengagewitheachother,allowingforaspecific,regularrelativemotionandshape,whichisknownasmeshing.ClassificationofGearsUsedfortransmissionbetweentwoparallelshaftsUsedfortransmissionbetweentwointersectingshaftsUsedfortransmissionbetweentwonon-parallelshaftsCylindrical

GearBevel

GearWormandWormGearClassificationofGears

Cylindricalgearsaregenerallyclassifiedbasedonthedirectionoftheirteeth,whichincludestraightteeth,helicalteeth,andherringboneteeth.Herringbone

Tooth

Cylindrical

GearHelical

Tooth

Cylindrical

GearStraightTooth

Cylindrical

GearStraightTooth

Cylindrical

GearStructureoftheGearTeethoftheGearHubSpokesWheelRimKeywayShaftHoleStraightTooth

Cylindrical

GearBasicTerminologyandSymbolsofStraightToothCylindricalGearsTipCircle(Diameterda)ThecirclethatpassesthroughthetopofeachtoothofthegeariscalledtheTipcircle.Itsdiameterisrepresentedbyda.RootCircle(Diameter

df)Thecirclethatpassesthroughtherootofeachtoothofthegeariscalledtherootcircle.Itsdiameterisrepresentedbydf.PitchCircle(Diameterd)Whenmachiningthegear,thecircleusedtodefinethegeartoothpitchiscalledthepitchcircle.Itsdiameterisrepresentedbyd.Atthepitchcircle,thewidthofthetoothslotisequaltothetooththickness.StraightTooth

Cylindrical

GearBasicTerminologyandSymbolsofStraightToothCylindricalGearsAddendumHeight

（ha）Theradialdistancebetweenthepitchcircleandtheaddendumcircleiscalledtheaddendumheight,representedbyha.Dedendum

Height

（hf）Theradialdistancebetweenthepitchcircleandtherootcircleiscalledthededendumheight,representedbyHf.TotalTooth

Height

（h）Theradialdistancebetweentheaddendumcircleandtherootcircleiscalledthetotaltoothheight,representedbyh.Itiscalculatedas:h=ha+hfStraightTooth

Cylindrical

GearBasicTerminologyandSymbolsofStraightToothCylindricalGearsPitch(p)Thearclengthbetweentwocorrespondingpointsonadjacentteethalongthepitchcircleiscalledthepitch.Itisrepresentedbyp.Thepitchiscalculatedas:p=

Tooth

Thickness(s)+Tooth

Width(e)Modulus(m)Themodulusisoneoftheimportantparametersofgears.Ifthenumberofteethonthegearisdenotedasz,thenthemodulusisdefinedas:z，thenthemodulusisdefinedas:

d=mzWheredisthepitchcirclediameter.StraightTooth

Cylindrical

GearModulusStandardModulusforCylindricalGears（GB/T1357-2008

）FirstSeries1，1.25，1.5，2，2.5，3，4，5，6，8，10，12，16，20，25，32，40，50SecondSeries1.125，1.375，1.75，2.25，2.75，3.5，4.5，5.5，(6.5)，7，9，11，14，18，22，28，35，45StraightTooth

Cylindrical

GearCalculationofVariousGearPartDimensionsPartIIIDrawingMethodsforStraight-ToothCylindricalGearsPARTIIISpecifiedDrawingMethodforaSingleGearGearBody:

Drawthebodyportionintrueprojection.Gear

Teeth:

Calculatethefollowing

diameters:d、da、df,Thendrawthetoothportionasfollows:Tipcircleandtipline:usethicksolidlines.Pitchcircleandpitchline:usechainlines(dash-dotlines).Rootcircleandrootline:usethinsolidlines;thesemaybeomittedifclaritypermits.PitchLineTipLineRootLineTipCirclePitchCircleUseasectionalviewforthefrontviewWhenthecuttingplanepassesthroughthegear’saxis,thegearteetharedrawnwithoutsectioning.Drawthetipcircleandtiplinewiththicksolidlines.Drawthepitchcircleandpitchlinewithchainlines(dash-dot).Drawtherootlinewiththicksolidlines;therootcirclemaybeomitted.

SpecifiedDrawingMethodforaSingleGearInthemeshingarea:

Intheviewperpendiculartothecylindricalgearaxis(representingacircleview),thetipcirclesofthetwomeshinggearsaredrawnwiththicksolidlines,withthetwocirclestangenttoeachother.Thetipcirclesinthemeshingareacanalsobeomitted,aslongasthetwocirclesremaintangent.Intheviewparalleltothecylindricalgearaxis:

Ifnotsectioned,thetiplineisomitted,andthepitchlineisdrawnwithathicksolidline.Inthenon-meshingarea:Drawthegearasasinglegear,followingtheprescribeddrawingmethodforindividualgears.RegulatedDrawingMethodforGearMeshingWhenthecuttingplanepassesthroughtheaxesoftwomeshinggears,inthemeshingarea,thepitchcircles(forstandardgears,thedividingline)ofthetwogearscoincideandaredrawnasadashedline.Therootlinesofbothgearsaredrawnasthicksolidlines,whilethetiplineofonegearisdrawnasathicksolidline,andthetiplineoftheothergearisdrawnasadashedlineoromittedaltogether.DrawingMethodattheMeshPoint0.25mTheclearancebetweenthetipandtherootis0.25m(wheremisthemodule).RegulatedDrawingMethodforGearMeshingSummaryofthislectureBasicKnowledgeofGears01DrawingMethodforaSingleStraight-ToothCylindricalGear02DrawingMethodfortheMeshingofTwoStraight-ToothCylindricalGears03ReflectionQuestionDrawthegearmeshassemblydiagrambasedonthegivenpartdimensions.主講人：趙慧、楊國星TianjinLightIndustryVocationalTechnicalCollege7.SectionView

PartIConceptoftheSectionalViewPARTIConceptoftheSectionalViewImagineusingacuttingplanetocutthroughacertainpartofamachinecomponentandonlydrawingthecross-sectionalshape.Thistypeofdrawingiscalledasectionalview,orsimplyacross-section.Asshowninthefigure:AAA-AAcross-sectionisoftenusedtorepresentthecross-sectionsofribs,spokes,keyways,holes,connectingplates,andthecross-sectionalshapesofvariousprofilesonmachinecomponents.DifferencesBetweenCross-sectionalViewandSectionalViewAsectionalviewshowstheprojectionofallstructuresbehindthecuttingplane.Across-sectionalviewonlyshowstheshapeofthecross-section.

PartIIExtractingCross-sectionalViewsPARTIIExtractingCross-sectionalViewsAcross-sectionalviewdrawnoutsidetheviewoutlineiscalledanextractingcross-sectionalview.I.Drawing

Specifications:1.

Theoutlineofanextractingcross-sectionalviewisdrawnwiththicksolidlinesandshouldbepositionedalongtheextensionlineofthecuttingsymbolwheneverpossible.Ifnecessary,theextractingcross-sectionalviewcanbeplacedinanothersuitablelocationandrotated.ExtractingCross-sectionalViews2.

Whenthecross-sectionalshapeissymmetric,theextractingcross-sectionalviewcanalsobedrawn